Omron SYSMAC C500-NC222-E, Руководство по эксплуатации

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9
5. In order to execute positioning by the semiclosed-loop method with ac-
celeration and deceleration, target positions are set consecutively in the
error counter for processing, thus enabling smooth acceleration and de-
celeration.
Desired
position
(pulses)
Error
counter
count
(pulses)
Speed
voltage
Time
Time
Time
6. The target position becomes the count for the error counter and controls
the motor by conversion to a speed voltage for the servomotor driver.
Thus, the position equals the total count of target positions (shaded area
in the figure), and the speed will depend on the desired position per unit
time.
Consider the following positioning system where millimeter is selected as the
unit:
N
V
P
L
M
Rotary encoder
Servomotor
Reduction gear
Moving object
Feed-screw pitch
Where:
N = rotary encoder resolution (pulse/rev)
M = reduction ratio
V
=
speed of moving object (mm/s)
P = feed-screw pitch (mm/rev)
L = distance moved (mm)
Simplified Positioning
System Design
Control System Principles
Section 1-6